case of" is out now. you see a bonus song at jimmykimmellive.com. i want to thank kourtney and kim kardashian. apologies to matt damon. tomorrow night, magic johnson, and music from antibalas. "nightline" is next. thanks for watching. good night. tonight on "nightline,"

vanished abroad. a young american mother disappears in the final days of her dream vacation. the only clues, surveillance videos and a final message home. hilary's next chapter. in her final days as secretary of state, hillary clinton opens up about benghazi, her health scare and how she's not ruling out running for president. the latest on the wild weather ripping across the heartland. the extreme wind, hail, and tornados set to strike from texas to michigan.

from washington, this is "nightline" with cynthia mcfadden. again, and thanks for joining us. tonight, the frantic

international search for the young american mother who suddenly vanished while traveling alone on a dream vacation. it was her first trip overseas, but right before she was supposed to return home to her husband and her two young boys in new york, she disappeared without a trace. abc's juju chang brings us the latest. >> reporter: it was the trip of a lifetime complete with artsy instagram posts from istanbul, that sarai sierra, an avid photographer, shared with her family in new york. but when they went to pick her up at the airport, they discovered to their horror that somewhere halfway around the world she simply vanished. >> i called united airlines. they stated that she didn't board the flight. >> reporter: tonight her husband steven is caught up in a gut wrenching global missing persons case. >> you know, you have so many thoughts going through your mind. you don't know what to think. you don't know what to believe. you don't know what to expect,

what's going to come out of this. >> reporter: it was a dream vacation she planned with a friend who dropped out at the last minute. her family says she had every reason to come home. she even cut her trip short because she missed her 11 and 9-year-old sons and she was eager to register for classes at a local college. >> i've been married to her for 14 years and my love for her is deeper than for any other individual. >> reporter: tonight these grainy surveillance videos could be the best lead investigators have as they scan for clues to the 33-year-old mom's disappearance. nothing seems amiss as she walks around a mall, eats alone in a food court. eerie images taken a day before she lost touch. >> was she seen having coffee with somebody? is there any surveillance of somebody walking in or out with her at a location? all of those are potential leads. >> reporter: the mystery deepens because sierra stayed in constant contact with her family through skype and instant messages. her last text was received last monday saying i'll be home

tomorrow, yay. and then digital silence. at the hostel where she was staying, turkish police found her clothes, her passport, even her medical cards and phone charger still in the room. the own told authorities he last saw sierra sunday afternoon. >> with her passport in the room, and i've heard even her cell phone was in the room, i don't like that combination, because that leads me to believe that someone was able to lure her out of the room. >> when i stop, i want you to get out of the car. >> reporter: the storyline seems like something out of a hollywood movie, "taken" and "taken 2", which even takes place in turkey, stars liam neeson as a father trying to rescue loved ones who get caught up in human trafficking. but that is more likely the stuff of entertainment, according to brad garrett. >> television tends to drive

people toward the sex trade, that someone could have grabbed her. is that possible? i suppose it is. i would focus on who are the sex offenders or people who have had histories of abducting women in and around istanbul in the areas where she was frequenting. >> reporter: at this point, every clue is precious. >> go through her camera. what are the last shots she had taken that may give you a direction? >> reporter: but investigators will probably want to talk to sarai's husband and brother who are both now in turkey working with authorities. the state department refused to comment other than to say they too are working the case with turkish national police. >> i know what the family is going through. they are trying hard to do the right thing and hoping someone is going to tell them here's what we need you to do. >> reporter: jeff's brother joe went missing in honduras in 2009. essentially he went on a boat and disappeared. >> yeah. that's it. whether it was a matter of

getting caught in an odd current, a heart attack, or it's equally likely that somebody decided they wanted the boat. >> reporter: but you'll never know. >> we will likely never know. >> reporter: jeff went into enormous debt searching for his lost brother and now runs a website that connects families and gives advice. the site has hundreds of registered loved ones looking for the dozens of people who seem to have dropped off the face of the earth while visiting exotic locales. there's a language barrier, there's a cultural barrier. it must be very difficult to get an investigation under way or advance it in some way. >> sure. again, that's where you think the state department will be of vital assistance. for the most part, they're not. they're very quick to tell you the limitations on what they can do. >> reporter: there's a little bit of blame the victim that goes on in this situation, isn't there? >> yeah, that happens a lot. the fact that you -- the first place you start seeing it is if there is news coverage, if you're fortunate enough to get news coverage to build awareness of your situation immediately, the internet trolls are on there

commenting with things like, must not want to be found. must have been up to no good and got something they had coming to them. that's probably the most heartbreaking thing. hope can be painful. >> reporter: perhaps the only thing more painful is having no hope at all. for "nightline," i'm juju chang in new york. just ahead, hillary clinton and her last television interview as secretary of state. she opens up about her personal health crisis, benghazi, and whether we should expect a white house bid from her in 2016. ♪ [ male announcer ] to hold a patent that has changed the modern world... would define you as an innovator. to hold more than one patent of this caliber... would define you as a true leader. ♪ to hold over 80,000... well, that would make you... the creators of the 2013 mercedes-benz e-class...

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she has met with world leaders 1,700 times in the past four years, but as of friday, hillary clinton will no longer be secretary of state. today, massachusetts senator john kerry was confirmed as her successor. i've interviewed secretary clinton nearly a dozen times and i've never seen her so relaxed or up beat. we sat down for her last television interview in office. no topic was off-limits. she's been secretary of state for four years. visited 112 countries. more than any of her predecessors. logged almost a million miles. but it's where she's going next that has everybody talking. let's just say this isn't the

first time the question has come up. in moscow three years ago, you told me, "i have absolutely no interest in running for president, none." you're never going to run for president again? >> i have absolutely no interest in running for president again. none, none. >> two years ago you said the exact same thing in australia. >> you said talk about the future. you said you're not running for president in 2012 or 2016 or 2020. and yet in the past few days, ready for hillary has been launched. can you still say with a straight face that there's no way you would consider running for president? >> sitting here now, that is certainly what i believe, and i am still the secretary of state, so i'm not in politics. i'm going to be focusing on my philanthropy, my charities, my writing and speaking.

so i am looking forward to having something resembling a normal life again. >> and yet, are we up to maybe? >> that's very good, cynthia. well, of course. of course, i am flattered and honored. i didn't even know about some of these things that are happening now. i don't know how else to say it, but i am going to get back into my life again. this is going to be new for me. i don't know how i'm going to react to it, to be honest. >> when you conceded defeat in the primary, you made a famous speech in which you said that there were 18 million cracks in the glass ceiling. >> although we weren't able to shatter that highest, hardest glass ceiling this time, thanks to you, it's got about 18 million cracks in it. [ cheers and applause ] >> if in the course of the next couple years it appears, as it does appear right now, that you might be the person who could actually breakthrough that glass ceiling and become the first female president of this

country, would you feel a certain obligation to seize that mantel? >> i do want to see that glass ceiling shattered. i don't think it has to be any particular person. >> but there's never been a woman who really had a credible chance. and it looks as if you might just be that person. and i know how seriously you take commitment and obligation. >> right. but i'm not making any commitments or obligations because i do take them seriously. >> we've been following clinton since her days in the senate, through awkward weeks as a presidential candidate in iowa. to the end of that road. and on to a new job that took her around the world. and over these years, an evolution, from grim determination, often wooden and cautious. >> i'm a more reserved person. >> to today. at ease. in on the joke. comfortable letting people hear that famous laugh. but a recent series of medical problems have been no laughing matter. when in early december, the

high-flying chief diplomat was grounded. well, it's good to see you looking so healthy. >> thank you, thank you. >> it really was a serious health scare. >> well, it was a big surprise to me because i've been so healthy for my entire life. so when i got sick and fainted and, you know, hit my head, i was so surprised. and i thought well, i'll just get up and go to work. and then, thankfully i had very good medical care and doctors said nope, we better do an mri and we better do this, we better do that. i'm getting fully recovered and i will be back to full speed. but i am grateful for the excellent care i got. >> so as one woman who wears glasses to another, i'll tell you what happens if i take mine off. i can't see my questions. if you take yours off right now? >> well, that would have been true even before i had a concussion. if i take mine off, you know, i've been nearsighted since i was 9.

>> this whole seeing double thing, is that true? >> well, i have some lingering effects from the concussion, but they will dissipate over the next weeks and i'll be back to my old myopic self. >> i know there's no plans for future public service, but if there were to be, would you feel comfortable making a pledge that you would release whatever records? >> oh, of course. that doesn't bother me. that's just something that goes with the territory. >> what else goes with the territory? something clinton is certainly familiar with -- harsh criticism and tough questions. she was called before congress last week and grilled over what she has called the low point in her tenure, the security lapse in benghazi, libya, that led to the death of four americans, including ambassador chris stevens. in the first days, the controversy reached a boiling point over this. >> there was a violent protest outside of our embassy. >> u.s. ambassador to the u.n. susan rice's explanation that the murders were the result of an anti-muslim video. that turned out to be false.

it was a pre-planned terrorist attack. in her testimony, clinton pulled no punches. >> we didn't know that. >> with all due respect, the fact is we had four dead americans. was it because they had protests, or because guys out for a walk they decided to kill americans. what difference at this point does it make? it is our job to figure out what happened and do everything question to prevent it from ever happening again, senator. >> and today, she doubled down. it seemed as though you lost your temper at the hearing. >> when someone tries to put it into a partisan lens, when they focus not on the fact that we had such a terrible event happening with four dead americans, but instead, what did somebody say on a sunday morning talk show? that to me is not in keeping with the seriousness of the issue and the obligation we all have as public servants. >> but do you regret what difference at this point does it make? >> no, because i think that asking questions about talking

points for a sunday morning talk show, is really missing the point. i believe in transparency. i said let the chips fall where they may. put it all out there. and i don't want that to be politicized. >> so you stand by what you said? >> absolutely. >> when we come back, the more intimate hillary on her family and her future. llenge. this is the age of knowing how to make things happen. so, why let erectile dysfunction get in your way? talk to your doctor about viagra. 20 million men already have. ask your doctor if your heart is healthy enough for sex. do not take viagra if you take nitrates for chest pain; it may cause an unsafe drop in blood pressure. side effects include headache, flushing, upset stomach, and abnormal vision. to avoid long-term injury, seek immediate medical help for an erection lasting more than four hours. stop taking viagra and call your doctor right away if you experience a sudden decrease or loss in vision or hearing. this is the age of taking action. viagra. talk to your doctor.

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there was a time not so very long ago when hillary clinton was seen as one of the most divisive figures in american politics. but after serving four years as secretary of state under her former rival barack obama, for some, that seems to be changing. we return now to my interview with her today in the jefferson room at the state department. as she exits the public stage, for now, anyway, secretary of state hillary clinton is basking in an approval rating of 66%, a lifetime high.

but that's not to say she's without her critics. among other things, the administration's handling of the ongoing blood bath in syria remains highly controversial. >> and it's time for assad to get out of the way. the united states believes that president assad should step away. the world will not waiver. assad must go. >> you repeatedly said that president assad needs to go. >> right. >> starting two years ago. >> right. >> and yet, 60,000 syrians are dead and he is still in office. >> right. >> what does it take for america to intervene? >> well, i think we have been very actively involved. until recently, there was no credible opposition coalition, and i cannot stress strongly enough how important that is. you cannot even attempt a political solution if you don't have a recognized force to counter the assad regime. >> secretary panetta recently

said that president assad had chemical weapons ready to go, locked and loaded, ready to go. the red line used to be when he moved those chemical weapons, and now would the u.s. actually permit him to use them? >> no, no. and president obama has been very clear about that. we laid down the red line on chemical weapons, because that could have far-reaching effects beyond even the street-to-street fighting that is so terrible to watch. and it could also affect other countries. >> the administration has been criticized by some for having what has been referred to as an ad hoc foreign policy, a sort of whack-a-mole. what is the obama doctrine as you understand it? >> reassert american leadership. politically and economically in the face of a very severe crisis that we inherited, which called into question american leadership. look for every way you can to bring together coalitions so that yes, america will and must

lead. it is the indispensable nation. but other countries have to step up and start taking responsibility and they are beginning to do that. >> so there's no daylight between the obama doctrine and the hillary clinton doctrine. >> well, i've been a major part of helping to shape it and to implement it. and i think it will stand the test of time. >> as we sat down to talk this afternoon -- >> john kerry of massachusetts to become our new secretary of state is confirmed. >> senator kerry has just been confirmed. >> yes, i'm thrilled by that. >> does that feel -- do you start to feel -- >> i do, i do. >> what do you wish you'd known four years ago that you could pass on? >> i don't see how you do this job without traveling a lot. condi rice traveled a million miles, and i traveled nearly that and went to more countries than anybody has gone to. and why do we do that? is it because we're glutens for punishment? no, because the united states has to show up. nothing substitutes for demonstrating that the united

states of america cares enough to be there, to be at that meeting, to represent our values. >> but as of friday, that will be john kerry's responsibility. saturday morning -- >> yes. >> what happens? >> i hope i get to sleep in. i'm thinking about that. because it will be the first time in many years when i've got no office to go to, no schedule to keep, no work to do. that will probably last a few days. and then i will be up and going with my new projects. >> thank you for much for talking to us. >> thank you, cynthia. good to talk to you. >> as jefferson looks over our shoulder, who i would only point out was secretary of state who went on to become president. >> i've heard that. thank you. >> our thanks to the secretary. and finally tonight, we turn to the extreme weather slamming much of the country. record high temperatures today are causing severe thunderstorms and damaging winds to rip across the south and midwest tonight, as a pow